About
* off-topic, newbies, marketplace and non-english boards are not included (details)
Charts released as CC-BY-SA.
Data and charts are updated every 17 minutes.
Sources: Blockexplorer,
Blockchain.info (Backup),
Dot-Bit.org (Backup),
Bitcoincharts,
Coinabul (buy gold for BTC),
MtGox,
Bitstamp
Note that the long term charts are a blend of MtGox (before 2013) and Bitstamp (from 2013-01-01).

Please note that there is no natural scale relationship between difficulty and price and the scales are chosen arbitrarily just to fit nicely.
The fit curve is an exponential percentual to the chart least squares fit - in other words: I played around
until it looked good.